The ultrastructure of cervical mucus

The physical and chemical characteristics of cervical mucus suggest a specific internal molecular configuration. Various investigators proposed that the molecular patterns occurring include the presence in the mucoid gel component of cervical mucus of long flexible threadlike molecules consisting of a polypeptide backbone with attached and branched sugar radicals. The pattern persisted in ovulatory midcycle mucus but changed to a dense meshwork configuration in the luteal phase of the menstrual cycle and in women taking oral progestational agents. A technique has been evolved to collect cervical mucus with minimal molecular distortion. Molecular patterns obtained by electron microscopic examination of the specimen corresponded to a surprising degree with the patterns previously predicted. The midcycle ovulatory mucus and the luteal-phase mucus showed distinctive patterns. Women taking the oral contraceptive progestagens showed varying patterns depending on the preparations used. It was suggested that the preliminary studies provide visual support for the proposed basic physical and chemical models of cervical mucus. (AUTHORS MODIFIED)